1. Technical Field
The present invention relates to an electro-optical device such as a liquid crystal device, to a method of manufacturing the same, to an electronic apparatus having the electro-optical device, such as a liquid crystal projector, and to a semiconductor device.
2. Related Art
In electro-optical devices, such as a liquid crystal device, a structure in which display pixels and driving circuits are simultaneously formed on the same substrate is used. In the above-mentioned structure, a serious problem does not occur even if an element characteristic, such as a transistor characteristic, of a semiconductor element that is provided at a display pixel and mainly performs a relatively low-speed switching operation is relatively low; however, an element characteristic of a semiconductor element that performs a relatively high-speed switching operation, a current amplification operation, a current control operation, a rectification operation, or a voltage holding operation in a driving circuit is required to be excellent. For this reason, there are disclosed various techniques in which single crystal silicon is used as a semiconductor layer of a semiconductor element of a driving circuit and polysilicon is used as a semiconductor layer of a semiconductor element of a display pixel. For example, a method of efficiently forming different kinds of semiconductor layers on the same substrate is disclosed in JP-A-5-134272. Specifically, JP-A-5-134272 discloses a technique in which a semiconductor layer is formed by growing a silicon layer with a silicon nitride layer as a seed layer and then it is determined whether the silicon layer to be deposited will be a polycrystalline silicon layer or a single crystal silicon layer by differently setting the size of the silicon nitride layer serving as the seed layer. Further, a method of converting a single crystal silicon layer to polysilicon is disclosed in JP-A-2001-255559. Specifically, JP-A-2001-255559 discloses a method of converting the single crystal silicon layer to polysilicon by injecting silicon ions into the single crystal silicon layer and then performing heat treatment, laser annealing, or the like.
However, in the technique disclosed in JP-A-5-134272, it is difficult to obtain a silicon layer having a sufficiently smooth surface, which causes a technical problem in which a planarization process, such as a CMP (chemical mechanical polishing), is additionally required. In addition, since it is difficult to grow the silicon layer from the seed layer, a technical problem occurs in that it is difficult to put the technique disclosed in JP-A-5-134272 to practical use. Furthermore, in the technique disclosed in JP-A-2001-255559, a technical problem occurs in that it is difficult to convert the single crystal silicon layer to polysilicon by injection of silicon ions.